Combustors are commonly used in industrial and power generation operations to ignite fuel to produce combustion gases having a high temperature and pressure. For example, turbo-machines such as gas turbines typically include one or more combustors to generate power or thrust. A typical gas turbine includes an inlet section, a compressor section, a combustion section, a turbine section, and an exhaust section. The inlet section cleans and conditions a working fluid (e.g., air) and supplies the working fluid to the compressor section. The compressor section progressively increases the pressure of the working fluid and supplies a compressed working fluid to the combustion section. A fuel is mixed with the compressed working fluid within the combustion section and the mixture is burned in a combustion chamber defined within the combustion section to generate combustion gases having a high temperature and pressure. The combustion gases flow to the turbine section where they expand to produce work. For example, expansion of the combustion gases in the turbine section may rotate a shaft connected to a generator to produce electricity.
The combustion section may include one or more combustors annularly arranged between the compressor section and the turbine section. In a particular combustor design, each combustor includes an end cover that is connected to an outer casing so as to form a high pressure plenum around the combustor. Each combustor also includes a plurality of bundled tube segments or sectors disposed downstream from the end cover. The plurality of bundled tube segments are generally arranged in an annular array about an axial centerline of the end cover and/or about an axially extending center fuel nozzle. Each bundled tube segment is fluidly connected to the end cover via a fluid conduit that extends axially downstream from the end cover.
Each bundled tube segment generally includes a plurality of parallel tubes arranged radially and circumferentially across the bundled tube segment. The parallel tubes extend generally axially through a fuel plenum defined within the bundled tube segment. The tubes provide for fluid communication through the fuel plenum and into the combustion chamber. One end of the fluid conduit is rigidly bolted to the end cover and a second end is fixedly or rigidly connected to the bundled tube segment, thereby creating an end loaded cantilever. As a result, the fluid conduit generally carries the structural load created by the cantilevered bundled tube segment at the connection joint defined at the end cover.
As the combustor cycles through various operating modes, the cantilevered bundled tube segments vibrate at various frequencies which may result in large deflections of the fluid conduit, thereby causing undesirable bending stresses at the end cover and fluid conduit connection joint. In addition, the vibrations may result in the adjacent bundled tube segments clashing together, thereby potentially resulting in durability issues. Therefore, an improved system for mounting and/or supporting the bundled tube segments within the combustor would be useful.